xml建模
建模的由来
就是将指定的xml字符串当作对象来操作
如果说当对一个指定的xml格式字符串完成了建模操作,
好处在于,只需要调用指定的方法就可以完成预定的字符串获取;
建模的思路
1、分析需要被建模的文件中有那几个对象
2、每个对象拥有的行为以及属性
3、定义对象从小到大(从里到外)
4、通过23种的设计模式中的工厂模式,解析xml生产出指定对象
好处:提高代码的复用性
java中的23种设置模式之一的工厂模式:
为什么要使用:能够提高代码的复用性
怎么去使用:只要建立一个方法,去生产指定的你需要的对象
用途:去生产指定的你需要的对象,以便重复使用
示例:
ConfigModel
查找、新增
package com.wangjing.model;
import java.util.HashMap;
import java.util.Map;
public class ConfigModel {
private Map<String, ActionModel> aMap=new HashMap<>();
/**
* 压栈
* @param forwardModel
*/
public void push(ActionModel actionModel) {
aMap.put(actionModel.getPath(), actionModel);
}
/**
* 弹栈
* @return
*/
public ActionModel pop(String name) {
return aMap.get(name);
}
}
ActionModel
属性、新增、查询
package com.wangjing.model;
import java.util.HashMap;
import java.util.Map;
public class ActionModel {
private String path;
private String type;
private Map<String , ForwardModel> fMap=new HashMap<>();
public String getPath() {
return path;
}
public void setPath(String path) {
this.path = path;
}
public String getType() {
return type;
}
public void setType(String type) {
this.type = type;
}
/**
* 压栈
* @param forwardModel
*/
public void push(ForwardModel forwardModel) {
fMap.put(forwardModel.getName(), forwardModel);
}
/**
* 弹栈
* @return
*/
public ForwardModel pop(String name) {
return fMap.get(name);
}
}
ForwardModel
属性
package com.wangjing.model;
public class ForwardModel {
private String name;
private String path;
private boolean redirect = true;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getPath() {
return path;
}
public void setPath(String path) {
this.path = path;
}
public boolean isRedirect() {
return redirect;
}
public void setRedirect(boolean redirect) {
this.redirect = redirect;
}
ConfigModelFactory,工厂模式:
package com.wangjing.model;
import java.io.InputStream;
import java.util.List;
import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;
public class ConfigModelFactory {
/**
* 默认资源文件MVC,xml是放在建模类的同包下
* @return
* @throws DocumentException
*/
public static ConfigModel build() throws DocumentException {
return build("mvc.xml");
}
/**
* 当资源文件,需要手动改变位置的情况下,那么需要调以下方法
* @param xmlPath
* @return
* @throws DocumentException
*/
public static ConfigModel build(String xmlPath) throws DocumentException {
ConfigModel configModel=new ConfigModel();
ActionModel actionModel=null;
ForwardModel forwardModel=null;
InputStream in= ConfigModelFactory.class.getResourceAsStream(xmlPath);
SAXReader reader=new SAXReader();
Document doc= reader.read(in);
List<Element> actionEles= doc.selectNodes("config/action");
for (Element actionEle : actionEles) {
actionModel=new ActionModel();
// 填充actionModel
actionModel.setPath(actionEle.attributeValue("path"));
actionModel.setType(actionEle.attributeValue("type"));
List<Element> forwardEles= actionEle.selectNodes("forward");
for (Element forwardEle : forwardEles) {
forwardModel=new ForwardModel();
// 填充forwardModel
forwardModel.setName(forwardEle.attributeValue("name"));
forwardModel.setPath(forwardEle.attributeValue("path"));
forwardModel.setRedirect(!"false".equals(forwardEle.attributeValue("redirect")));
actionModel.push(forwardModel);
}
configModel.push(actionModel);
}
return configModel;
}
public static void main(String[] args) throws DocumentException {
ConfigModel configModel=ConfigModelFactory.build();
ActionModel actionModel =configModel.pop("/loginAction");
System.out.println(configModel.pop("/loginAction").getType());
System.out.println(actionModel.pop("success").getPath());
}
}
运行结果:
建模分两步:
1、以面向对象的编程思想,描述xml资源文件
2、将xml文件中内容封装进model实体对象。
注:属性为String类型,子元素标签则是map的值,子元素标签的唯一标识则为map的值
练习:
1、对web.xml进行建模
2、写一个servlet
3、通过url-pattern读取到servlet-class的值
web.xml代码:
<?xml version="1.0" encoding="UTF-8"?>
<web-app>
<servlet>
<servlet-name>jrebelServlet</servlet-name>
<servlet-class>com.zking.xml.JrebelServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>jrebelServlet</servlet-name>
<url-pattern>/jrebelServlet</url-pattern>
</servlet-mapping>
<servlet>
<servlet-name>jrebelServlet2</servlet-name>
<servlet-class>com.zking.xml.JrebelServlet2</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>jrebelServlet2</servlet-name>
<url-pattern>/jrebelServlet2</url-pattern>
<url-pattern>/jrebelServlet3</url-pattern>
</servlet-mapping>
</web-app>
ServletNameModel代码:
package com.wangjing.model;
public class ServletNameModel {
private String context;
public String getContext() {
return context;
}
public void setContext(String context) {
this.context = context;
}
}
ServletClassModel代码:
package com.wangjing.model;
public class ServletClassModel {
private String context;
public String getContext() {
return context;
}
public void setContext(String context) {
this.context = context;
}
}
UrlPatternModel代码:
package com.wangjing.model;
public class UrlPatternModel {
private String context;
public String getContext() {
return context;
}
public void setContext(String context) {
this.context = context;
}
}
ServletModel代码:
package com.wangjing.model;
public class ServletModel {
private ServletNameModel servletNameModel;
private ServletClassModel servletClassModel;
public ServletNameModel getServletNameModel() {
return servletNameModel;
}
public void setServletNameModel(ServletNameModel servletNameModel) {
this.servletNameModel = servletNameModel;
}
public ServletClassModel getServletClassModel() {
return servletClassModel;
}
public void setServletClassModel(ServletClassModel servletClassModel) {
this.servletClassModel = servletClassModel;
}
}
ServletMappingModel代码:
package com.wangjing.model;
import java.util.ArrayList;
import java.util.List;
public class ServletMappingModel {
private ServletNameModel servletNameModel;
private List<UrlPatternModel> urlPatternModels=new ArrayList<>();
public ServletNameModel getServletNameModel() {
return servletNameModel;
}
public void setServletNameModel(ServletNameModel servletNameModel) {
this.servletNameModel = servletNameModel;
}
public void pushUrlPatternModel(UrlPatternModel urlPatternModel) {
urlPatternModels.add(urlPatternModel);
}
public List<UrlPatternModel> getUrlPatternModels(){
return urlPatternModels;
}
}
WebAppModel代码:
package com.wangjing.model;
import java.util.ArrayList;
import java.util.List;
public class WebAppModel {
private List<ServletModel> servletModels=new ArrayList<>();
private List<ServletMappingModel> servletMappingModels=new ArrayList<>();
public void pushServletModel(ServletModel servletModel){
servletModels.add(servletModel);
}
public List<ServletModel> getServletModels(){
return servletModels;
}
public void pushMappingModel(ServletMappingModel servletMappingModel){
servletMappingModels.add(servletMappingModel);
}
public List<ServletMappingModel> getServletMappingModels(){
return servletMappingModels;
}
}
WebAppModelFactory代码:
package com.wangjing.model;
import java.io.InputStream;
import java.io.Reader;
import java.util.ArrayList;
import java.util.List;
import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.Element;
import org.dom4j.io.SAXReader;
public class WebAppModelFactory {
public static WebAppModel builAppModel() throws DocumentException {
String xmlPath="web.xml";
return builAppModel(xmlPath);
}
/**
* 建模
* @param xmlPath
* @return
* @throws DocumentException
*/
public static WebAppModel builAppModel(String xmlPath) throws DocumentException {
InputStream in=WebAppModelFactory.class.getResourceAsStream(xmlPath);
SAXReader reader=new SAXReader();
WebAppModel webAppModel=new WebAppModel();
Document doc= reader.read(in);
/*
*将servlet的标签内容填充进WebApp
*/
List<Element> servletEles=doc.selectNodes("/web-app/servlet");
for (Element servletEle : servletEles) {
ServletModel servletModel=new ServletModel();
/*
*给servletModel填充xml内容
*/
Element servletNameEle=(Element) servletEle.selectSingleNode("servlet-name");
Element servletClassEle=(Element) servletEle.selectSingleNode("servlet-class");
ServletNameModel servletNameModel=new ServletNameModel();
ServletClassModel servletClassModel=new ServletClassModel();
servletNameModel.setContext(servletNameEle.getText());
servletClassModel.setContext(servletClassEle.getText());
servletModel.setServletNameModel(servletNameModel);
servletModel.setServletClassModel(servletClassModel);
webAppModel.pushServletModel(servletModel);
}
/*
* 将servlet-mapping的标签填充进WebApp
*/
List<Element> servletMappingEles=doc.selectNodes("/web-app/servlet-mapping");
for (Element servletMappingEle : servletMappingEles) {
ServletMappingModel servletMappingModel=new ServletMappingModel();
/*
* 给ServletMappingModel填充xml的内容
*/
Element servletNameEle=(Element) servletMappingEle.selectSingleNode("servlet-name");
ServletNameModel servletNameModel =new ServletNameModel();
servletNameModel.setContext(servletNameEle.getText());
servletMappingModel.setServletNameModel(servletNameModel);
List<Element> urPatternEles=servletMappingEle.selectNodes("url-pattern");
for (Element urPatternEle : urPatternEles) {
UrlPatternModel urlPatternModel=new UrlPatternModel();
urlPatternModel.setContext(urPatternEle.getText());
servletMappingModel.pushUrlPatternModel(urlPatternModel);
}
webAppModel.pushMappingModel(servletMappingModel);
}
return webAppModel;
}
/**
* 通过浏览器输入的网址自动找到对应的后台处理类
* @param webAppModel 建模后的实体类
* @param url 浏览器访问的网址
* @return
*/
public static String getServletClassByUrl(WebAppModel webAppModel,String url) {
String servletClass="";
/*
* 找到浏览器网址对应的servlet-name
*/
String servletName="";
List<ServletMappingModel> servletMappingModels=webAppModel.getServletMappingModels();
for (ServletMappingModel servletMappingModel : servletMappingModels) {
List<UrlPatternModel> urlPatternModels=servletMappingModel.getUrlPatternModels();
for (UrlPatternModel urlPatternModel : urlPatternModels) {
if(url.equals(urlPatternModel.getContext())) {
ServletNameModel servletNameModel = servletMappingModel.getServletNameModel();
servletName=servletNameModel.getContext();
}
}
}
/*
* 找到servlet-name对应的后台处理类
*/
List<ServletModel> servletModels=webAppModel.getServletModels();
for (ServletModel servletModel : servletModels) {
ServletNameModel servletNameModel=servletModel.getServletNameModel();
if(servletName.equals(servletNameModel.getContext())) {
ServletClassModel servletClassModel=servletModel.getServletClassModel();
servletClass = servletClassModel.getContext();
}
}
return servletClass;
}
}
运行代码:
public static void main(String[] args) throws DocumentException {
WebAppModel webAppModel = WebAppModelFactory.builAppModel();
String res = getServletClassByUrl(webAppModel, "/jrebelServlet");
String res2 = getServletClassByUrl(webAppModel, "/jrebelServlet2");
String res3 = getServletClassByUrl(webAppModel, "/jrebelServlet3");
System.out.println(res);
System.out.println(res2);
System.out.println(res3);
}
}
运行结果: